Buy a quality barrel, fairly expensive,
and reassemble the rifle with the new barrel....add an aftermarket trigger, 2.5 to 3 lb... It will probably shoot as good as any. Properly assembled, checked and squared, it will probably shoot 1/2 moa 5 shot groups fairly often. Total cost about $650.
I just built an AR 15 in 30 RAR from parts left over, from other builds... the barrel was a Rem 700 26" police factory barrel with 8000rds on it. Cut off the chamber with most of the firecracking, shortened, and profiled the 700 barrel to AR 15, installed a used barrel nut, gas block was the wrong size, so it was had an insert pressed in and bored to size. Chambered threaded, gas journal turned, and later gas port drilled.
Total cost was like $340 including the reamer. It shoots very well for an AR made from used, and left over parts. Plus making the brass, there is no 30 RAR brass, chamber gauges, etc for this obsolete caliber.
Learn to build you own and reload for it, ya don't have to do extensive rifle building, but it all helps.